The point of upbraiding this monk for his question is that the energy being spent here would be better spent somewhere else. Nearly anywhere else. Asking "which way of doing almost nothing is faster, and maintainability be damned" is a bad attitude and deserves criticism. The method of concatenation will not be the performance bottleneck in any mod_perl script that does anything of significance. Stas was criticized by several people on the list for doing this benchmark, since it only serves to fuel this kind of counterproductive behavior. People need to learn how to do it right: build it, profile it, fix the slow parts, repeat.